Gas turbine plant equipped with regulating apparatus



Dec. 15, 1942.

C5. JENDRRSSIK GAS TURBINE PLANT EQUIPPED'WITH REGULAT ING APPARATUS Filed July 5, 1938 W/fhesses:

5 Sheets-Sheet 1 In venf a r 1942- G. JENDRASSIK ,30

GAS TURBINE PLANT EQUIPPED WITH REGULATING APPARATUS Filed July 5, 1938 3 Sheets-Sheet 2 v In venforw 1942- G. JENDRASSIK 2,305,311

GAS TURBINE PLANT'EQUIPPED WITH REGULATING APPARATUS Filed July 5, 1938 3 Sheets-Sheet 3 Fig.5

Witnesses In venlor:

Patented Dec. 15, 19 42 GAS TURBINE PLANT EQUIPPED WITH REGULATING APPARATUS George Jendrassik, Budapest, Hungary; vested in the Alien Property Custodian Application July 5, 1938, Serial No. 217,506 a In Hungary July 7, 1937 3 Glaims. (Cl. 60'-41) Proposals for the regulationof gas turbines are known according to which, in order to keep the 'tempe'r'atureof the gas turbineplant at a suitable figure at diminishing outputs, provision is made,'simultaneously with the'diminution of the quantity of fuel burntper revolution, for diminishing also, by throttlingthe suction pressure of the compressor compressing the working medium, the quantity of airsuppliedby the compressor, in consequence whereof. the temperature of the working medium expanding in the turbine need not be diminished in' case of diminishing output either. A very great drawback of these proposals consists in the fact that-the throttling employed in the suction duct. of the compressor is in itself causing a very substantial loss of work, and thus the advantage represented by the maintenance ofthe temperature of the working medium expandingin the turbine is in a great extent offset by the loss of work referred the case of this method the losses bearing any relation to the: magnitude of the quantity of air, e. g..thelossees of the heat exchange device serving for heating the compressed working medium 'and'for'cooling down the gases leaving the turh-ine will also diminish. Particularly suitable for performing the regulation will be a type of compressor in which the mean diameter of any stationary or rotating blade ring will, at least approximately, be equal to 'the average of the mean diameters of the two blade rings adjacent to it,

such as an axial throughflow, or a radial throughu of the compressor.

The regulating apparatus forming the subject of the invention eliminates this drawback in such a manner that it ma'kes provision, in the case of the working medium, of the blades which is di-' v minished, and therefore such deflection influcences'the efllciency of,- the stage or of stages in question but does "not cause any extra loss. It will be preferable to vary the quantity of fuel introduced and the quantity of air supplied by the compressor in such a manner as toensure that the temperature of the working medium entering any stage of the turbineshould remain unchanged also with widely varying outputs; this will enable the thermal efficiency of the plant to be kept at a high figure at low outputs also.

The deflection of the blades of the compressor will exert a double effect; on the one hand it will tend to reduce the proportion of pressures produced in the stage in question, and on the other hand-in so far as the deflection of the blades in'the case of diminishing'outputs takes place so as to start from the low-pressure stages of the compressor-it will also tend to reduce the volume drawn in by the compressor. This latter method of regulation is more advantageous, as in around the pivot I0 is engaging.

named'lever is, through the pull-rod I2, connect- The apparatus forcarrying out the process of I regulation into effect is shown in two different variants or partial sections, respectively,-by Figs. 1 and 2, of which Fig. '1 shows the deflection of the blades being effected by means of a speed governor, whilst Fig. 2 shows the performance of the same deflection by means of a thermostat.

Figs. 3 and 4 exemplify a mechanism serving for the performance of the deflection of the blades,

finally, Fig. 5 illustrates, in cross-section, the fuel nozzle and the combustion chamber of the gas turbine in the case of its being fed with liquid fuel.

In the embodiment shown by way-of example on Fig. '1 it is on the compressor 3, driven from the turbine I by means of the shaft 2, that the centrifugal governor 4 reacting to the number of revolutions per minute of the set is arranged.

The oscillating masses 5 and 6 of the centrifugal governor are able to oscillate around the pivots I, I and are supported by means of lever transmissions on the sleeve 8 of the governor, on which sleeve the spring 9 is also acting. It is with the sleeve 8 that the lever II journalled This lasted with the lever I3, which operates a mechanism, shown in Figs. 3 and 4, for deflecting the blades of the compressor.

Of these figures, Fig. 3 shows the axial section of the blade rings of'the compressor, the said section being taken through the pivot 39 of the lever I3, whereas Fig. 4 shows the view, developed into a plane of the mechanis'memployed for deflecting the blades. The arrangement as shown by way of example is one in which it is the blades of the blade ring 31 of the pressure stage of lowest pressure, i. e. of the first pressure stage that the deflecting mechanism is able to deflect, whereas the stationary blade ring 31" together with further stationary blade rings fixed in dove tail guides in the casing 35, and the stationary blade ring 31 arranged in front of the flrst stage and serving purely for guiding the working fluid admitted, as well as the rotating blade rings 33, 38 .etc. fixed in the rotor 36 cannot be deflected. The lever l3 acts, as shown in Figs. 3 and 4, directly through the pivot 39 of the said lever on one of the blades of the blade ring 31', whereas the displacement in an entirely identical extent of the other blades of this blade ring is effected by means of the forked arm 40 flxed on the pivot 39 of the lever l3 and by means of the adjusting collar 4|, the forked arm 4|) mentioned acting on the pivot 42 of the adjusting collar 4| and the motion transmitted from further pivots 42 of the adjusting collar set in motion in the manner described on the other blades of the blade ring 31 also by means of forked arms 40 of mutually identical construction. That sense of rotation of the adjusting collar 4| which belongs to the sense of rotation 43 (corresponding to diminishing output) of the lever I3 is marked 45, whilst the sense of deflection of the pivots 39 and thereby of the blades 31' corresponding to the sense of rotation 43 of the lever I3 is marked 44.

The compressor draws in the working medium through the tube |4,and discharges it in com-. pressed condition through the pipeline IS. The compressed working medium discharged from the compressor is preferably led through the heat exchange device IS, in which it is heated by means of the gases discharged from the turbine to nearly the temperature of the latter. Before the compressed working medium enters the turbine through 'the inlet duct l1, it will in the example shown absorb heat, owing to the combustion of fuel, in the combustion chamber |8 shown in horizontal crossssection in Fig. 5. After heat transmission the working medium expands in the turbine and leaves the latter through the duct I9, from which it passesv into the heat exchange device ii, in which latter it becomes its contents of heat cooled down, transmitting to the fresh quantity of working medium, and will leave the plant through the duct 20. In the turbine casing the thermostat 2| reacting on the temperature of the working medium is arranged so as to be in contact with the working medium entering the turbine. In the example shown this thermostat is constructed as a gas thermometer,

the closed gas space 22 of which communicates with the space below the membrane 23 through the duct 24. It is on the membrane 23 that the rod 25 is supported, which latter is connected with the double-arm lever 21 journalled around the pivot 26. The doi-ible-armlever 21, on the other hand, acts through the pull-rod 28 on the lever 29 of the device regulating the quantity of fuel burnt in the working medium, 1; e. introduced into the latter. According to Fig. the nozzle body 46 into the storage space of which the fuel--in this case shown by way of example liquid fuel-is being supplied by the pipe line 49, is mounted on the combustion chamber Ill. The nozzle body contains the needle valve 41 on the free end projecting from the nozzle body of which the lever 29 acts in a direct manner. The valve rod of the needle valve possesses a threaded part 48 with the aid of which the needle-valve can be displaced in its axial direction in the thread cut into the nozzle body when operating the lever 29 and thereby the opening of the needle valve may be made smaller or greater (smaller if the temperature acting on the thermostat rises) so as to suit the conditions of operation.

The operation of ,this regulating device is the following: The thermostat 2| is keeping the temperature of the working medium more or less constant owing to the fact that any possible increase of the temperature will cause the membrane of the thermostat to become displaced under the action of the rise of pressure taking place in the interior of the thermostat, which pressure is transmitted by the rod 25, the doublearm lever 21 and the pull-rod 28 to the lever 29, thereby influencing the quantity of heat introduced into the working medium in the direction of diminishing the said quantity. In this arrangement of connections, accordingly, it is the thermostat or temperature regulator 2| which ensures that the fluctuation of the temperature of the working medium should not exceed the amount of variations permitted, whilst the centrifugal governor 4 ensures that the number of revolutions per minute of the set of machinery should not'exceed the permitted limits. Should in case of the diminution of the load the number of revolutions per minute of the set of machinery rise, the centrifugal governor 4 will with the aid of the lever H and of the pull-rod l2 adjust the lever |3 in such a manner as to ensure that the proportion of pressures produced by the compressor, i. e. the quantity of working medium supplied by the compressor should diminish. This stage of regulation will, whilst keeping the quantity of fuel introduced unchanged, cause a rise of temperature in the vicinity of the thermostat,

and therefore after the function of regulation in question the thermostat will become operative and will diminish the quantity of fuel burnt.

The embodiment shown by way of example in Fig. 2 differs from the preceding one only in so far that there it is not the quantity of heat that is regulated by the thermostat 2| with the aid of the double-arm lever 30 and the pull-rod 3|, but it is the blades of the compressor that are being deflected by the said thermostat directly or indirectly by means of the lever 32. On the other hand, the centrifugal governor 4 exerts through the lever 34 a regulating action on the quantity of fuel burnt. In the case of this arrangement the course of regulation in the case of diminishing load is the following: The centrifugal governor 4 diminishes, by means of the pull-rod 33 and of the lever 34, the quantity of heat introduced. Thereby the temperature in the vicinity of the thermostat 2| diminishes, and

the thermostat will, through the lever 3|! and the pull-rod 3|, position the lever 32, or, respectively, the blades of the compressorinsuch a manner as to ensure that the proportion of pressures produced by the compressor, i.-' e.-the quantity of air supplied by the compressor will diminish, whereby the thermostat exercises an influence in the opposite direction on the diminution of the temperature. j Y

Of course, the described types of apparatus serving for the regulation of the temperature or of the number of revolutions per minute represent only exemplifying embodiments without limitation-for the general case, all that is important being that these devices should be on the variations of the temperature, or respectively of the number of revolutions per minute.

In consequence hereof the invention relates also to all such types of design or arrangements as have not been detailed in thespeciiication,

able to react asoaau 1. In a gas turbine plant, a gas turbine, a ro-.

fary compressor compressing the working medium for the gas turbine, means introducing heat by fuel combustion into the compressed working medium, a thermostat, reacting on temperature,

variations, in contact with the previously heated working medium of the gas turbine, a device regulating the quantity of fuel to be burnt, being operatively connected with the said'thermostat, a device suitable for deflecting the stationary blades of at least some stages of the compressor, and a speed governor reacting on the number of revolutions P. M. of the turbine, being operatively connected with the said device suitable for deflecting the compressor blades in such a manner that in case of increasing number of revolutions the angle of attack of the deflected blades should be diminished.

her of revolutions P. M. of the turbine, being operatively connected with the said device regulating the fuel quantity, and a device suitable for deflecting the stationary blades of the compressor, being operatively connected with the said I thermostat in such a manner that in case of decreasing temperature the angle of attack of the.

deflected blades should also be diminished.

3. In a gas turbine plant, a gas turbine, a rotary compressor compressing the working medium for the gas turbine, means introducing heat by fuel combustion into the compressed working medium, a thermostat, reacting on temperature variations, in contact with the previ-' ously heated working medium of the gas turbine, a device regulating the quantity of fuelto be burnt, a device suitable for deflecting the sta- 2. In a gas turbine plant, a gas turbine, a rotary compressor compressing the working medium for the gas turbine, means introducing heat by fuel combustion into the compressed working medium, a thermostat, reacting on temperature variations, in contact with the previously heated working medium of the gas turbine, a device regulating the quantity of fuel to be burnt, a speed governor reacting on the numtionary blades of at least some stages of the compressor, and a speed governor reacting on the number of revolutions P. M. of the turbine, the said thermostat being operatively connected with the one, and the said speed governor with the other of the said devices suitable for deflecting the blades and for regulating the fuel quantity in such a manner that in case of diminishing output theangle of attack of the deflected blades should be, together with the diminution of fuel supply, diminished.

GEORGE JENDRASSIK. 

